1. Field of Invention
This invention relates to civionics and, in particular, to an apparatus, system and method for detecting defects in building structures.
2. Description of Related Art
Detecting and locating defects such as leaks in building structures, including detecting and locating leaks in low-slope roofs of buildings, can assist in the development, repair, maintenance and appraisal of such building structures. With the introduction of green roofs, leaks are even more detrimental and difficult to locate as water is intentionally held on the roof within landscaping materials.
Leaks in building structures may be detected by visual inspection; however, leaks are not always visible or may not become visible until after such leaks have caused damage to the structure. Also, visible effects of a leak may be located distally from the leak, thereby failing to accurately indicate the location of the detected leak. The accuracy of leak detection by visual inspection depends on the skill and experience of the person conducting the visual inspection. Visual inspection alone does not provide a transmittable record of the location nor size of a visually detected leak.
Leaks in a low-sloped roof of a building may be detected by flood testing in which a large body of water is maintained on the roof for a long time period, such as several days, while water level changes are monitored and visual inspections for leaked water are periodically performed. However, such periodic visual inspections alone do not provide a transmittable record of the location nor size of a visually detected leak.
Leaks in a low-sloped roof may be detected by use of a negative pressure container placed in contact with a liquid distributed over a section of the roof, such that visible bubbles are created where leaks exist. However, the mere appearance of visible bubbles do not provide a transmittable record of the location nor size of the detected leak.
Leaks in a low-sloped roof can be detected by injecting smoke into a positive pressure region created beneath the roof and visually inspecting the upper surface of the roof for escaping smoke. However, the mere appearance of escaping smoke does not provide a transmittable record of the location nor size of the detected leak.
An indication of the possibility of a leak in a building structure may be obtained by measuring the humidity of materials of the structure. However, an abnormal humidity level does not necessarily indicate the presence of a leak, as it may indicate the presence of a spill or other cause instead. Also, a leak in a structure often causes a section of the structural materials much larger than the size of the leak to have increased humidity, thereby failing to accurately locate the leak.
U.S. Pat. No. 4,565,965 issued Jan. 21, 1986 to Geesen discloses a method and apparatus for locating leaks in flat roofs, in which electrical pulses are transmitted along a moisture path through a leak and along the wetted flat roof to the roof edge. The wetted flat roof is scanned by sensors made of a pair of rods connected to a display scale indicating the magnitude of electrical current through the rods. The magnitude becomes greater as the leak location is approached.
Training and experience are required by a skilled technician in order to detect and locate a leak using the method and apparatus of Geesen. Accordingly, the accuracy and completeness in detecting and locating leaks is dependent on the skills, training and experience of the technician using the method and apparatus of Geesen. The method and apparatus of Geesen does not facilitate the analysis of multiple measurements; does not provide a transmittable record of the location nor value of a measurement being taken; and does not provide a transmittable record of the location nor size of any detected leaks.
U.S. Pat. No. 4,543,525 issued on Sep. 24, 1985 to Boryta et al. discloses a method for determining a leak in a flat roof. A grounding electrode is attached to the reinforcing steel rods in concrete supporting the roof, roof drains are plugged, and the roof is flooded with an electrically conductive fluid such as salt water to a depth of several inches. An electrical potential is established between the fluid and the support structure. Boryta et al. also disclose a leak detector for determining a leak in a pond liner of electrically insulating material. The leak detector has a pair of spaced apart probes electrically connected to each other through a galvanometer for measuring electrical current through the probes. Detecting and locating a leak requires multiple successive measurements. The leak detector may be handheld, or in the form of a tripod supported by wheels and provided with undisclosed means for pulling or pushing the detector across the pond.
Training and experience are required by a skilled technician in order to detect and locate a leak using the method and leak detector of Boryta et al. Accordingly, the accuracy and completeness in detecting and locating leaks is dependent on the skills, training and experience of the technician using the method and leak detector of Boryta et al. The leak detector of Boryta et al. does not facilitate the analysis of multiple measurements; does not provide a transmittable record of the location nor value of a measurement being taken; and does not provide a transmittable record of the location nor size of any detected leaks.
Canadian patent No. 2,613,308 to Vokey discloses a method and apparatus for locating a leak in a membrane on top of a horizontal roof deck. The leak is located by sweeping over the upper surface of the membrane with a manually operable carriage. A measuring and switching circuit generates a voltage having a positive attached to the roof deck and a negative attached to conductive brushes on the carriage. The conductive brushes include an outer set of conductive brushes for detecting the leak at distance from the leak and an inner conductive brush for detecting the leak when the carriage is directly over the leak.
Training and experience are required by a skilled technician in order to detect and locate a leak using the method and apparatus of Vokey. Accordingly, the accuracy and completeness in detecting and locating leaks is dependent on the skills, training and experience of the technician using the method and apparatus of Vokey. The apparatus of Vokey does not facilitate the analysis of multiple measurements; does not provide a transmittable record of the location nor value of a measurement being taken; and does not provide a transmittable record of the location nor size of any detected leaks.
United Kingdom patent application publication No. 2,393,517 to Neil Graham Ferguson Adams discloses an instrument for locating defects in non-conductive materials. The instrument includes a handheld, mobile component connected to a stationary component by a multi-conductor lead. The handheld component includes a central probe surrounded by four outer probes, all of which are fixed to a non-conductive supporting plate. The probes may be telescopic and spring-loaded. On top of the plate are situated eight lines of light emitting diodes (LEDs), each line being at 45° to the previous. The stationary component includes a pulsing power supply connected between earth, or ground, of the non-conductive material and the central probe of the handheld component. The potential difference between each pair of diametrically opposite probes is found and, depending on their relative magnitude, a net vector representing the direction of current flow is calculated. This is quantized to the nearest 45° and the line of LEDs corresponding to this angle illuminated.
However, the instrument as described by Adams is limited in resolution to eight lines of LEDs; does not facilitate the analysis of multiple measurements taken in sequence; does not provide a transmittable record of the location nor value of a measurement being taken; and does not provide a transmittable record of the location nor size of any detected leaks.
An object of the invention is to address the above shortcomings.